Ballpoint pen



FIG. 1 is a front perspective view of a ballpoint pen showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a left side elevational view thereof; the right side elevational view being a mirror image of the left side;

FIG. 4 is a rear view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a front perspective view thereof in open position; and,

FIG. 8 is a rear perspective view thereof in open position. 

The ornamental design for a ballpoint pen, as shown and described. 